LED lighting fixture

FIELD OF THE INVENTION

p-0002This invention relates to light fixtures. More particularly, this invention relates to light fixtures which utilize light-emitting diodes (LEDs) as the light source.

BACKGROUND OF THE INVENTION

p-0003In recent years, the use of LEDs for various common lighting purposes has increased, and this trend has accelerated as advances have been made in LEDs and in LED-array devices, often referred to as “LED modules.” Indeed, lighting applications which have been served by fixtures using high-intensity discharge (HID) lamps and other light sources are now increasingly beginning to be served by LED fixtures. Creative work continues in the field of using LEDs for light fixtures in various applications.

p-0004High-luminance light fixtures using LEDs as the light source present particularly challenging problems. High cost due to high complexity becomes a particularly difficult problem when high luminance, reliability, and durability are essential to product success. Keeping electronic LED drivers in a water/air-tight location may also be problematic, particularly when the light fixtures are constantly exposed to the elements.

p-0005Dealing with heat dissipation requirements is still another problem area for high-luminance LED light fixtures. Heat dissipation is difficult in part because high-luminance LED light fixtures typically have many LEDs. Complex structures for module mounting and heat dissipation have sometimes been deemed necessary, and all of this adds complexity and cost.

p-0006Furthermore, previous fixtures utilizing HID lamps and other non-LED light sources typically require a comparatively large lamp compartment with large reflectors for lighting efficiency. Such fixtures often also require large ballast compartments. These often result in large overall fixture size and a substantially heavy fixture.

p-0007In short, there is a significant need in the lighting industry for improved light fixtures and the like using LEDs. There is a need for fixtures that satisfy the problems associated with heat dissipation and appropriate protection of electronic LED driver components. Finally, there is a need for an improved LED-module-based light which is relatively simple, compact and easy and inexpensive to manufacture.

OBJECTS OF THE INVENTION

p-0008It is an object of the invention to provide an improved LED lighting fixture that overcomes some of the problems and shortcomings of the prior art, including those referred to above.

p-0009Another object of the invention is to provide an improved LED lighting fixture that is readily adaptable for a variety of mounting positions and situations.

p-0010Another object of the invention is to provide an improved LED lighting fixture with both good protection of electronic LED drivers and excellent heat dissipation from LEDs and drivers.

p-0011Yet another object of the invention is to provide an improved LED lighting fixture providing desirable illumination.

p-0012Still another object of the invention is to provide an improved LED lighting fixture which is relatively simple and compact.

p-0013How these and other objects are accomplished will become apparent from the following descriptions and the drawings.

SUMMARY OF THE INVENTION

p-0014The present invention is an improvement in LED lighting fixtures. The inventive LED lighting fixture includes a housing having a hollow interior cavity defined by a backwall and a surrounding wall extending therefrom to a forward edge. An LED illuminator is mounted in the housing. And, an LED-support structure extends in the interior cavity from the housing to an LED-supporting surface which positions the LED illuminator in a desired orientation and is spaced from the backwall.

p-0015The LED-support structure is a heat sink transferring heat from the LED illuminator to the housing. It is preferred that the LED-support structure is substantially spaced from the surrounding wall. The LED lighting fixture preferably includes at least one interior rib connecting the LED-support structure to the surrounding wall.

p-0016In preferred embodiments of the inventive LED lighting fixture, the outer surface of the housing includes a series of fins extending outwardly therefrom. The fins provide further heat dissipation from the LED illuminator.

p-0017In some of such embodiments, the LED-support structure extends from the backwall. The housing and the LED-support structure may be preferably integrally formed with the outer surface of the backwall having a region free of outer fins. The housing and the LED-support structure are preferably formed by casting. It is preferred that a finned insert is secured to such region of the backwall free of outer fins such that the rear of the fixture is uniformly finned.

p-0018In preferred embodiments, the LED-support structure extends from the backwall. Such LED-support structure is preferably substantially hollow. And, the backwall has an aperture leading into the hollow LED-support structure which allows passage of wiring into the housing interior and to the LED illuminator. The hollow LED-support structure preferably defines an aperture into the housing interior for the passage of wiring into the housing interior from the backwall aperture.

p-0019The LED lighting fixture preferably includes an LED driver within the housing interior. It is preferred that the LED driver be secured against the housing, thereby transferring heat from the driver.

p-0020The backwall may be substantially planar with the surrounding wall including a wire passage into the housing interior. In such embodiments, a plurality of similar fixtures may be mounted along a mounting surface and powered with daisy-chain wiring.

p-0021In some preferred embodiments, the LED-supporting surface supports the LED illuminator substantially at the level of the forward edge of the surrounding wall. The LED lighting fixture preferably includes a cover closing the housing interior. Such cover may be made of suitable metal to serve as an electrical closure for the housing interior. The cover defines an LED aperture exposing the LED illuminator. It is preferred that the cover have a substantially white outer surface to reduce absorption of incident light.

p-0022The LED lighting fixture preferably includes a lens member over the LED illuminator and sealingly connected to the housing. The lens member preferably includes a lens portion configured for broad distribution of LED-emitted light and a flange portion about the lens portion. The housing preferably includes an outward collar about the forward edge of the surrounding wall. The flange portion of the lens member sealingly engages the outward collar to provide a weather seal to the housing interior. The LED lighting fixture may include a flange-adjacent gasket between the flange portion and the outward collar.

p-0023The LED illuminator is preferably a multi-chip LED module. The module may be a type of LED packages which include twenty five LEDs compactly placed close together and coated by a layer of phosphorus selected to produce different colors of white light such as warm, neutral and cool white light. Such LED packages are highly energy-efficient and have a long operating life.

p-0024These packages are compact, high-flux-density light sources. The compact size of such multi-chip LED packages is also highly desirable. They are typically round or square with a diameter or a side length of about 20-26 millimeters and a depth of about 3.5 millimeters. The relatively small dimensions of these modules permit significant reduction in the dimensions of lighting fixtures which utilize such high-luminance compact LED light sources.

p-0025Certain embodiments of the inventive LED lighting fixture further include a reflector cup which is positioned at the LED-supporting surface and surrounds the LED illuminator to reflect LED-emitted light in a desired direction. The LED-supporting surface is preferably positioned such that distal edges of the reflector cup are substantially at the level of the forward edge of the surrounding wall.

p-0026It is preferred that the LED lighting fixture of further includes a lens member over the LED illuminator and sealingly connected to the housing. The lens member may include a light-transmissive region over the reflector cup for transmitting LED-emitted light and a opaque region covering the housing interior.

p-0027The lens member is preferably substantially planar. It is preferred that the housing includes an outward collar about the forward edge of the surrounding wall. The lens member preferably sealingly engages the outward collar. The LED lighting fixture may further include a collar-adjacent gasket between the lens member and the outward collar.

p-0028In some alternative embodiments, the LED-supporting surface supports the LED illuminator at an acute angle with respect to the backwall.

p-0029The surrounding wall may includes a shield portion in position to intercept a portion of emitted light.

BRIEF DESCRIPTION OF THE DRAWINGS

p-0030<figref idrefs="DRAWINGS">FIG. 1</figref> is a front perspective view of one preferred embodiment of the LED lighting fixture in accordance with this invention.

p-0031<figref idrefs="DRAWINGS">FIG. 2</figref> is a rear perspective view of the LED lighting fixture of <figref idrefs="DRAWINGS">FIG. 1</figref>.

p-0032<figref idrefs="DRAWINGS">FIG. 3</figref> is a perspective view of an interior cavity of the LED lighting fixture of <figref idrefs="DRAWINGS">FIG. 1</figref>.

p-0033<figref idrefs="DRAWINGS">FIG. 4</figref> is an exploded view of the LED lighting fixture the LED lighting fixture of <figref idrefs="DRAWINGS">FIG. 1</figref>.

p-0034<figref idrefs="DRAWINGS">FIG. 5</figref> is a front perspective view of a second preferred embodiment of the LED lighting fixture in accordance with this invention.

p-0035<figref idrefs="DRAWINGS">FIG. 6</figref> is a rear perspective view of the fixture of <figref idrefs="DRAWINGS">FIG. 5</figref>.

p-0036<figref idrefs="DRAWINGS">FIG. 7</figref> is a perspective view of an interior cavity of the LED lighting fixture of <figref idrefs="DRAWINGS">FIG. 5</figref>.

p-0037<figref idrefs="DRAWINGS">FIG. 8</figref> is an exploded view of the LED lighting fixture the LED lighting fixture of <figref idrefs="DRAWINGS">FIG. 5</figref>.

p-0038<figref idrefs="DRAWINGS">FIG. 9</figref> is a front perspective view of a third embodiment of the LED lighting fixture in accordance with this invention.

p-0039<figref idrefs="DRAWINGS">FIG. 10</figref> is a rear perspective view of the fixture of <figref idrefs="DRAWINGS">FIG. 9</figref>.

p-0040<figref idrefs="DRAWINGS">FIG. 11</figref> is an exploded view of the LED lighting fixture of <figref idrefs="DRAWINGS">FIG. 9</figref>.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

p-0041<figref idrefs="DRAWINGS">FIGS. 1-11</figref> illustrate preferred embodiments of an inventive LED lighting fixture <b>10</b>. As best seen in <figref idrefs="DRAWINGS">FIGS. 3</figref>, <b>4</b>, <b>7</b>, <b>8</b> and <b>11</b>, lighting fixture <b>10</b> includes a housing <b>20</b> having a hollow interior cavity <b>21</b> defined by a backwall <b>22</b> and a surrounding wall <b>23</b> extending therefrom to a forward edge <b>24</b>. An LED illuminator <b>11</b> is mounted in housing <b>20</b>. And, an LED-support structure <b>30</b> extends in interior cavity <b>21</b> from housing <b>20</b> to an LED-supporting surface <b>31</b> which positions LED illuminator <b>11</b> in a desired orientation and is spaced from backwall <b>22</b>.

p-0042LED-support structure <b>30</b> is a heat sink transferring heat from LED illuminator <b>11</b> to housing <b>20</b>. LED-support structure <b>30</b> is spaced from surrounding wall <b>23</b>. LED lighting fixture <b>10</b> also includes three interior ribs <b>12</b> connecting LED-support structure <b>30</b> to surrounding wall <b>23</b>.

p-0043The outer surface <b>25</b> of housing <b>20</b> includes a series of fins <b>26</b> extending outwardly therefrom. Fins <b>26</b> provide further heat dissipation from LED illuminator <b>11</b>.

p-0044<figref idrefs="DRAWINGS">FIGS. 3</figref>, <b>4</b>, <b>7</b>, <b>8</b> and <b>11</b> further show LED-support structure <b>30</b> extending from backwall <b>22</b>. It is seen in <figref idrefs="DRAWINGS">FIG. 4</figref> that LED-support structure <b>30</b> is substantially hollow. And, <figref idrefs="DRAWINGS">FIG. 2</figref> illustrates backwall <b>22</b> with an aperture <b>220</b> leading into hollow LED-support structure <b>30</b> which allows passage of wiring (not shown) into housing interior <b>21</b> and to LED illuminator <b>11</b>. <figref idrefs="DRAWINGS">FIGS. 3 and 4</figref> also show that hollow LED-support structure <b>30</b> defines an aperture <b>32</b> into housing interior <b>21</b> for the passage of wiring into housing interior <b>21</b> from backwall aperture <b>220</b>.

p-0045LED lighting fixture <b>10</b> includes an LED driver <b>15</b> within housing interior <b>21</b>. LED driver <b>15</b> is secured against housing <b>20</b> thereby transferring heat from driver <b>15</b>.

p-0046<figref idrefs="DRAWINGS">FIG. 3</figref> illustrates backwall <b>22</b> being substantially planar and surrounding wall <b>23</b> including a wire passage <b>230</b> into housing interior <b>21</b>. Such configuration allows a plurality of similar fixtures to be mounted along a mounting surface, i.e., a wall, ceiling or other suitable surface, and to be powered with daisy-chain wiring.

p-0047In the embodiment shown in <figref idrefs="DRAWINGS">FIGS. 1-4</figref>, LED-supporting surface <b>30</b> supports LED illuminator <b>11</b> substantially at the level of forward edge <b>24</b> of surrounding wall <b>23</b>. As best illustrated in <figref idrefs="DRAWINGS">FIG. 4</figref>, LED lighting fixture <b>10</b> includes a cover <b>16</b> closing housing interior <b>21</b>. Such cover may be made of suitable metal to serve as an electrical closure for the housing interior. Cover <b>16</b> defines an LED aperture <b>160</b> exposing LED illuminator <b>11</b>. Cover <b>16</b> has a substantially white outer surface <b>161</b> to reduce absorption of incident light. <figref idrefs="DRAWINGS">FIGS. 3 and 4</figref> further show an illuminator cover <b>17</b> which is mounted immediately over LED illuminator <b>11</b> and defines a light aperture <b>170</b> sized substantially to match dimensions of a light-illuminating portion of LED illuminator <b>11</b>.

p-0048LED lighting fixture <b>10</b> includes a lens member <b>40</b> over LED illuminator <b>11</b> and is sealingly connected to housing <b>20</b>. Lens member <b>40</b> includes a lens portion <b>41</b> configured for broad distribution of LED-emitted light and a flange portion <b>42</b> about lens portion <b>41</b>. Lens portion <b>41</b> includes a series of faucets <b>410</b> to refract LED-emitted light. Lens portion <b>41</b> is formed by a frontwall <b>43</b> and sidewalls <b>44</b> extending transversely therefrom. Flange portion <b>42</b> extends outwardly from sidewalls <b>44</b>. Housing <b>20</b> includes an outward collar <b>28</b> about forward edge <b>24</b> of surrounding wall <b>23</b>. Flange portion <b>42</b> of lens member <b>40</b> sealingly engages outward collar <b>28</b> to provide a weather seal for housing interior <b>21</b>. LED lighting fixture <b>10</b> includes a flange-adjacent gasket <b>47</b> between flange portion <b>42</b> and outward collar <b>28</b>.

p-0049Inventive LED lighting fixture <b>10</b>A shown in <figref idrefs="DRAWINGS">FIGS. 5-8</figref> includes a reflector cup <b>50</b> which is positioned at LED-supporting surface <b>31</b> and surrounds LED illuminator <b>11</b> to reflect LED-emitted light in a desired direction. In this embodiment, LED-supporting surface <b>31</b> is positioned such that distal edges <b>51</b> of reflector cup <b>50</b> are substantially at the level of forward edge <b>24</b> of surrounding wall <b>23</b>.

p-0050<figref idrefs="DRAWINGS">FIGS. 5-8</figref> illustrate fixture <b>10</b>A having two LED illuminators <b>11</b> and including two reflector cups <b>50</b>, one for each LED emitter <b>11</b>. In this embodiment, LED-support structure <b>30</b>A is positioned across interior cavity <b>21</b>A substantially in the middle thereof. Internal ribs <b>12</b>A extend between two opposite ends of LED-support structure <b>30</b>A and an adjacent side of surrounding wall <b>23</b>A. The embodiment shown in <figref idrefs="DRAWINGS">FIGS. 5-8</figref> has a round back which is formed by the backwall smoothly transitioned into opposite sides of the surrounding wall.

p-0051Housing <b>20</b> and LED-support structure <b>30</b> are formed by casting with LED-support structure <b>30</b> extending from backwall <b>22</b>. Housing <b>20</b> and LED-support structure <b>30</b> are integrally formed with outer surface <b>25</b> of backwall <b>22</b>. Backwall <b>22</b> has a region <b>27</b> free of outer fins <b>26</b>. It is seen in <figref idrefs="DRAWINGS">FIG. 6</figref> that a finned insert <b>13</b> is secured to and filling fin-free region <b>27</b> of backwall <b>22</b> such that rear <b>14</b> of fixture <b>10</b>A is uniformly finned. Line <b>271</b> indicates the interface between fin-free region <b>27</b> and finned insert <b>13</b>.

p-0052<figref idrefs="DRAWINGS">FIGS. 9-11</figref> illustrate LED lighting fixture <b>10</b>B which has LED-supporting surface <b>31</b>B at an acute angle with respect to backwall <b>22</b> to support LED illuminator <b>11</b> at an angle for a desired orientation of LED-emitted light.

p-0053LED lighting fixtures <b>10</b>A and <b>10</b>B further include lens frames <b>46</b>A (see <figref idrefs="DRAWINGS">FIG. 8) and 46B</figref>, respectively, over LED illuminator <b>11</b> and sealingly connected to housing <b>20</b>. As seen in <figref idrefs="DRAWINGS">FIGS. 5</figref>, <b>8</b>, <b>9</b> and <b>11</b>, lens frames <b>46</b>A and <b>46</b>B each include a light-transmissive region <b>48</b> for transmitting LED-emitted light and an opaque region <b>49</b> covering housing interior <b>21</b>.

p-0054In LED lighting fixture <b>10</b>B, light-transmissive region <b>48</b> is formed by an aperture through a cover plate <b>49</b> which forms the opaque region surrounding the aperture. Lens member <b>40</b>B overlays cover plate <b>49</b>.

p-0055In fixture <b>10</b>A, lens frame <b>46</b>A is substantially planar. It is also seen in <figref idrefs="DRAWINGS">FIGS. 7 and 8</figref> that housing <b>20</b> includes an outward collar <b>28</b> about forward edge <b>24</b> of surrounding wall <b>23</b>. Lens frame <b>46</b>A sealingly engages outward collar <b>28</b>. LED lighting fixture <b>10</b>A further includes a collar-adjacent gasket <b>45</b> (seen in <figref idrefs="DRAWINGS">FIGS. 7 and 8</figref>) between lens frame <b>46</b>A and outward collar <b>28</b>.

p-0056<figref idrefs="DRAWINGS">FIG. 9</figref> illustrates surrounding wall <b>23</b>B including a shield portion <b>55</b> in position to intercept a portion of emitted light.

p-0057While the principles of the invention have been shown and described in connection with specific embodiments, it is to be understood that such embodiments are by way of example and are not limiting.